ascertain
Cross references: 1. discover as.cer.tain \.as-*r-'ta-n\ \-'ta--n*-b*l\ \-'ta-n-m*nt\ vt [ME acertainen, fr. MF acertainer, fr. a- (fr. L ad-) +] certain archaic 1: to make certain, exact, or precise 2: to find out or learn with certainty - as.cer.tain.able aj